Patents: The Clear and Convincing evidentiary standard required to rebut the presumption of patent validity will not be met when the key corroborative witness testimony is predicated on the challenging party’s own sequence of events.

Patents: Simple determination of optimum ranges for operation, and development of more comprehensive explanations of variable relationship based on broad ranges of prior art, does not qualify as non-obvious.

Patents: The differentiation doctrine presumption is particularly strong in cases where a limitation is the sole differentiation between claims and one party is asserting a dependent claim on an independent claim.

Patents: In discerning obviousness, the court looks to whether one of ordinary skill would have had reasonable motivation to modify the earlier claimed compound to make the compound of the asserted claim.